51981925 has 6 divisors (see below), whose sum is σ = 64457618. Its totient is φ = 41585520.

The previous prime is 51981911. The next prime is 51981959. The reversal of 51981925 is 52918915.

51981925 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 1940449 + 50041476 = 1393^2 + 7074^2 .

It is a de Polignac number, because none of the positive numbers 2^k-51981925 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1039614 + ... + 1039663.

Almost surely, 2^51981925 is an apocalyptic number.

It is an amenable number.

51981925 is a deficient number, since it is larger than the sum of its proper divisors (12475693).

51981925 is a wasteful number, since it uses less digits than its factorization.

51981925 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2079287 (or 2079282 counting only the distinct ones).

The product of its digits is 32400, while the sum is 40.

The square root of 51981925 is about 7209.8491662447. The cubic root of 51981925 is about 373.2078637859.

The spelling of 51981925 in words is "fifty-one million, nine hundred eighty-one thousand, nine hundred twenty-five".